[HECnet] LQA system ID message

[Johnny Billquist]

On 2013-02-16 22:45, Paul_Koning at Dell.com wrote:

On Feb 15, 2013, at 9:24 PM, Johnny Billquist wrote:

On 2013-02-16 03:03, Paul_Koning at Dell.com wrote:
The thing to do would be to see what happens if you load some multicast address (such as broadcast) into slot 0 of the 16-entry address match table, and the station address into slot 1.   For a QNA, that's perfectly fine because all slots are equivalent and the device doesn't do any MOP.   It may be that this was a later restriction that RSTS didn't obey.   Or it may be a bad assumption in the real LQA that wasn't documented -- or maybe it's just a bad assumption in the SIMH emulation.   I haven't yet looked for LQA manuals to give more clues.

Ah. I thought you had already checked documentation.

Well, I did now, and simh is right. Page 3-31 of the DELQA manual states that the first address is used as the source address for system ID messages.

Which edition?   I'm looking at EK-DELQA-UG-002 (from Bitsavers) and it can't find anything like that.

The very same.
Page 3-31, Section 3.6.2.4, third paragraph:

"Any columns not used should be set to the physical address (for better protection against mischievous Ethernet traffic). More than one physical address may be specified, but in Normal mode, only the first is used for receiving datagrams, and as the source address for system ID messages generated by the DELQA."

So I guess RSTS/E just sets it up wrong.

More precisely, RSTS/E is written to DEQNA specs, which don't constrain which address goes where.

Right.

I guess I should see about constructing a patch for this.

That would maybe be a good deed. :-)

	Johnny

-- 
Johnny Billquist                                   || "I'm on a bus
                                                                  ||   on a psychedelic trip
email: bqt at softjar.se                         ||   Reading murder books
pdp is alive!                                         ||   tryin' to stay hip" - B. Idol